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![Spatial distribution (by density) of the percentage of infestation notification by triatomines in 2010, 2012, and 2016 in the state of Sergipe, Brazil. The hatching municipalities were considered at high risk for transmission of CD by the Sergipe State Health Department [37].](publication/328026374/figure/fig3/AS:1086459251564565@1636043479706/Spatial-distribution-by-density-of-the-percentage-of-infestation-notification-by.jpg)
Spatial distribution (by density) of the percentage of infestation notification by triatomines in 2010, 2012, and 2016 in the state of Sergipe, Brazil. The hatching municipalities were considered at high risk for transmission of CD by the Sergipe State Health Department [37].
Source publication
Updated information of the dispersion dynamics of Chagas disease (CD) and a systemic analysis of these data will aid the early identification of areas that are vulnerable to transmission and enable efficient intervention. This work synthesized spatiotemporal information regarding triatomine fauna and analyzed this information in combination with th...
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Approximately 150 triatomine species are known to be infected with the Chagas parasite, Trypanosoma cruzi, but they differ in the risk they pose to human populations.
The largest risk comes from species that have a domestic life cycle and these species have been targeted by indoor residual spraying campaigns, which have been successful in many loca...
Approximately 150 triatomine species are suspected to be infected with the Chagas parasite, Trypanosoma cruzi, but they differ in the risk they pose to human populations. The largest risk comes from species that have a domestic life cycle and these species have been targeted by indoor residual spraying campaigns, which have been successful in many...
Citations
... Over the last few years, extensive chemical control of triatomines in households has led to the absence of T. cruzi transmission by Triatoma infestans in Brazil 3 . However, other species (e.g., Panstrongylus lutzi, Panstrongylus megistus, Triatoma brasiliensis, and Triatoma pseudomaculata) continue to play an essential role in T. cruzi transmission 4,5 . Most present an invasive behavior already found in domestic and peridomestic environments in regions endemic for CD 6,7 . ...
Background
We assessed the distribution of triatomines in an endemic area for Chagas disease.
Methods
This retrospective study used secondary data extracted from the Official System of the National Chagas Disease Control Program (Sistema Oficial do Programa Nacional de Controle da Doença de Chagas - SisPCDCh).
Results
A total of 7,257 (725.7 ± 221.7 per year) specimens were collected from 2013 to 2022. Most of them (6,792; 93.6%) were collected in the intradomicile and 465 (6.4%) in the peridomicile. A total of 513 (7.1%) triatomines tested positive for the presence of trypomastigote forms, similar to Trypanosoma cruzi.
Conclusions
The spatial analysis revealed a heterogeneous distribution of triatomines across different municipalities.
Keywords:
Triatominae; Panstrongylus; Triatoma; Infection rate; Spatial distribution; Trypanosomatidae
... No Brasil, esta última forma de transmissão tem predominado devido ao avanço da urbanização, melhora nos métodos de controle da via vetorial e pela precariedade nos métodos de controle na produção dos alimentos como o açaí e a cana de açúcar (Melo et al., 2018). ...
... Por outro lado, a destruição do habitat e o estabelecimento de habitações humanas recém construídas em áreas endêmicas pode resultar em um deslocamento de espécies de mamíferos silvestres para áreas urbanas ou semiurbanas e, consequentemente, na domesticação de triatomíneos antes localizados em áreas silvestres(Coura & Junqueira, 2012;Melo et al., 2018).Este fato traz como consequência um aumento de triatomíneos domésticos, os quais passam a utilizar-se de animais como cães, gatos, tatus e gambás urbanizados como fontes de alimento, aumentando-se também a possibilidade de diversificação nos mecanismos de transmissão de tal parasitose(Bern et al., 2019;Dias et al., 2008;Enriquez et al., 2014;Freitas et al., 2022;Jansen et al., 2018;Roque et al., 2013).Cabe destacar que, como já foi mencionado, os próprios hospedeiros silvestres infectados podem vir a contaminar frutas com suas secreções, fator este que pode elevar o risco de infecção por ingestão de tais frutas ou de suas polpas. À exemplo dessa diversificação, os gambás, marsupiais didelfiídeos podem contaminar os alimentos e superfícies através de secreções e sua ação tem uma correlação com surtos de DCO (Henao-Martínez et al., 2017; Jansen et al., 2020). ...
A doença de Chagas persiste como uma importante parasitose que afeta a humanidade, sendo classicamente transmitida por excrementos de triatomíneos, as quais são depositadas na pele durante a hematofagia, permitindo assim a penetração de formas evolutivas do protozoário Trypanosoma cruzi. Tal via de transmissão tem sido sobreposta pela transmissão oral, haja vista diversos fatores, dentre os quais o controle de populações de triatomíneos e melhorias habitacionais, bem como o aumento do consumo de alimentos, com destaque para frutas amazônicas, à exemplo do açaí. Sendo assim, objetivou-se demonstrar e discutir a relevância da transmissão da doença de Chagas por via oral, e investigar aspectos relacionados a esse processo, de forma a suscitar possíveis estratégias para minimizá-la. Para tanto, realizou-se um estudo transversal retrospectivo em um período de 10 anos (2011-2020) com abordagem quantitativa, por meio da coleta e processamento de dados disponibilizados em sites governamentais. Observou-se que a via de transmissão oral persiste como a principal forma de aquisição da DCO no Brasil, como maior incidência de casos na região Norte, provavelmente por se tratar de uma região tradicionalmente produtora e consumidora de frutas amazônicas, como açaí e cupuaçu. Destaca-se neste sentido a importância de implantar métodos e estratégias de prevenção voltadas para os processos extrativos e de beneficiamento de frutas amazônicas e de outros alimentos potencialmente contamináveis por excreções de triatomíneos, a exemplo da introdução ou do reforço da adesão a técnicas de esterilização de alimentos como o branqueamento e a high isostatic pressure - HIP.
... The species of triatomines responsible for the transmission of Chagas disease has a wide distribution and can easily adapt to household environments. The colonization of triatomines occurs due to constant changes in the natural environment caused by anthropic activities that have led to an imbalance in the ecosystem and a modification of vector behavior [1][2][3] . ...
... The T. brasiliensis and T. pseudomaculata species were the most frequent in the study, indicating their vector potential in endemic regions, especially in or near households in rural areas 2,29 . In our study, these vectors were naturally infected in the Agreste and Sertao regions; these results are consistent with results from other studies conducted in Northeastern Brazil 29,30 . ...
This study aimed to analyze the spatial pattern of natural infection index (NII) for triatomines and the risk of Chagas disease transmission in an endemic area of Northeastern Brazil. An ecological study was conducted, based on 184 municipalities in five mesoregions. The NII for triatomines was evaluated in the Pernambuco State, Brazil, from 2016 to 2018. Spatial autocorrelations were evaluated using Global Moran Index (I) and Local Moran Index (II) and were considered positive when I > 0 and p < 0.05, respectively. In total, 7,302 triatomines belonging to seven different species were detected. Triatoma brasiliensis had the highest frequency (53%; n = 3,844), followed by Triatoma pseudomaculata (25%; n = 1,828) and Panstrongylus lutzi (18.5%; n=1,366). The overall NII was 12%, and the higher NII values were P. lutzi (21%) and Panstrongylus megistus (18%). In the mesoregions of Zona da Mata, Agreste, Sertao, and Sertao do Sao Francisco, 93% of triatomines were detected indoors. The global spatial autocorrelation of I to NII was positive (0.2; p = 0.01), and II values calculated using BoxMap, MoranMap, Lisa Cluster Map were statistically significant for natural infections. With regard to the risk areas for the presence of triatomines, Zone 2 (the Agreste and Sertao regions) presented a relative risk of 3.65 compared to other areas in the state. Our study shows the potential areas of vector transmission of Chagas disease. In this study, the application of different methods of spatial analysis made it possible to locate these areas, which would not have been identified by only applying epidemiological indicators.
Chagas disease; Epidemiology; Triatomine; Spatial analysis
... Geographic distribution. Central and South America (Melo et al. 2018). ...
... Armadillos. Zoonotic on humans (Melo et al. 2018). ...
The classification of “parasites” in the medical field is a challenging notion, a group which historically has included all eukaryotes exclusive of fungi that invade and derive resources from the human host. Since antiquity, humans have been identifying and documenting parasitic infections, and this collective catalog of parasitic agents has expanded considerably with technology. As our understanding of species boundaries and the use of molecular tools has evolved, so has our concept of the taxonomy of human parasites. Consequently, new species have been recognized while others have been relegated to synonyms. On the other hand, the decline of expertise in classical parasitology and limited curricula have led to a loss of awareness of many rarely encountered species. Here, we provide a comprehensive checklist of all reported eukaryotic organisms (excluding fungi and allied taxa) parasitizing humans resulting in 274 genus-group taxa and 848 species-group taxa. For each species, or genus where indicated, a concise summary of geographic distribution, natural hosts, route of transmission and site within human host, and vectored pathogens are presented. Ubiquitous, human-adapted species as well as very rare, incidental zoonotic organisms are discussed in this annotated checklist. We also provide a list of 79 excluded genera and species that have been previously reported as human parasites but are not believed to be true human parasites or represent misidentifications or taxonomic changes.
... (25) It has been demonstrated previously that areas with very degraded forests have little or no wild triatomine presence. (26) A drastic reduction of the T. cruzi infection in wild mammals, such as opossum, is also an indication of the absence of triatomines in very deforested regions. (27) This suggests that, in our study area, a tropical dry forest region with a history of strong deforestation driven by economic activities like monocultures and cattle pastures, the forest coverage does not currently influence the infestation and reinfestation patterns of T. dimidiata because the degradation and deforestation have reached a point where there are no surviving wild vector populations. ...
BACKGROUND
Deforestation, driven by anthropogenic change in land use, influences the behaviour and abundance of vector-borne diseases. For various species of Chagas disease vectors, there is evidence that change in land use affects population density and abundance. Triatoma dimidiata is the most important Chagas vector in Guatemala, and at least one million people live in T. dimidiata endemic areas; however, infestation dynamics vary among regions, from high infestation with all life stages to low seasonal infestation by sylvatic adults.
OBJECTIVES
The aim of this study was to evaluate how land-use, combined with domiciliary risk factors, influences the infestation dynamics of T. dimidiata for four villages in a dry forest region with a strong deforestation history.
METHODS
Land use, measured with drone and satellite images, was classified into four categories (houses, monocultures and pastures, woodland and shrubland, and bare soil). Domiciliary risk factors and infestation were assessed through entomological surveys. Statistical analyses compared infestation indices and the ability of land use and domiciliary risk factors to explain infestation.
FINDINGS
Two villages had significantly higher infestation (26 and 30% vs. 5 and 6%), yet all villages had high colonisation (71-100% of infested houses had immature insects), with no significant difference among them. Because of the high level of deforestation across the study area, land use was not related to infestation; however, domiciliary risk factors were. A model based on four weighted domiciliary risk factors (adobe or bajareque walls, intradomicile animals, intradomicile clutter, and dirt floors) explains the infestation risk.
MAIN CONCLUSIONS
Because almost all infested houses have reproducing populations in this deforested dry forest region and statistical analysis identified the domiciliary risk factors for infestation, intermediate and long-term control of Chagas disease vectors in this region requires management of these risk factors.
... For instance, in the Southeast region, P. megistus has been retrieved in urban areas 10 , while in the South Brazil, Triatoma circummaculata and Triatoma rubrovaria 11 have been reported as the most commonly detected species. In the Northeastern region species such as Triatoma brasiliensis, Panstrongylus lutzi and Triatoma pseudomaculata are frequently reported 7,9,12 . It is important to note that several natural environments in this region (e.g., xerophilous trees and rocks) are inhabited by triatomines 13 . ...
... The dispersion of triatomines in different environments may be related to mating or a search for food 19 . In this study, the presence of nymphs intradomicile indicates the formation of colonies in these environments represented by the phenomenon of domiciliation, and consequently high risk for human infection 7,12 . ...
... Various species were captured during the study (i.e., P. lutzi, T. brasiliensis, T. pseudomaculata and P. megistus), with P. lutzi being the most frequent (30.36%). This species had been already detected in other Brazilian regions 12,17 , and is relevant for the persistence of CD in endemic areas 21 . From an epidemiological perspective, P. lutzi plays a crucial role in the dynamic of T. cruzi infection in Northeastern Brazil, since it feeds on a wide plethora of hosts (e.g., birds, rodents, marsupials, dogs, goats, and humans), many of which are commonly found within the study area 9 . ...
Introduction:
Trypanosoma cruzi is the etiological agent of Chagas disease (CD), a zoonotic infection transmitted by triatomine bug vectors to human beings. Although the story of this parasitic infection was born in Brazil and here this has made major step forward information, the same cannot be said about the actual distribution of the triatomine vector in several areas of this country. The aim of this study was to assess the occurrence of triatomine species in an endemic region for CD in Northeastern Brazil.
Methods:
A retrospective study was performed using data obtained from 2008 to 2017. All information was provided by the V Gerência Regional de Saúde of the state of Pernambuco. The spatial distribution of triatomine species was analyzed by drawing a map using the Quantum geographic information system.
Results:
A total of 4,694 triatomine specimens (469.4 ± 221.2 per year) were collected during the period 2008-2017, with 94.5% (4,434/4,694) at the intradomicile and 5.5% (260/4,694) at peridomicile environment. Of all arthropods collected, 92.5% (4,340/4,694) and 7.5% (354/4,694) were adults and nymphs, respectively. The species most frequently detected were Panstrongylus lutzi (30.36%), Triatoma brasiliensis (26.12%), Triatoma pseudomaculata (22.43%), and Panstrongylus megistus (20.54%).
Conclusions:
These data contribute to a better understanding of the distribution of T. cruzi infection in the Northeastern region of Brazil. Preventive measures based on vector control should be implemented in the study area in order to reduce the burden this neglected tropical disease.
